Raise our Conscience against the Killing of RTI Activists

Wednesday, June 9, 2010

Good Logical Puzzle

Xavier has one of the numbers 1, 2, or 3 in mind. Peter is allowed to ask
one question to Xavier to find out which of these three numbers he has
in mind. Xavier will answer this question only with the answers "yes",
"no", or "I don't know".Which question should Peter ask Xavier to
find out in one time, which number he has in mind?

Answers are expected as comments.


  1. divide the no. with previous no. in the numerical order and check whether the answer is 2
    --->if ans is YES then number in Xavier's mind is 2(2/1=2)
    --->if N0, number is 3(3/2!=2)
    --->if dont know,number is 1 because 1/0 is not defined

  2. As per the question what prevents Xavier from saying I do not know for cases 1 and 2 in the mentioned answer.

  3. How can you say u don't know, when u know the answer. that is simple cheating.

  4. Yes there is nothing that prevents Xavier from cheating. Else you should have called it out in the question that Xavier will tell no lies.